• Journal of The Korean Association For Science Education
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• v.38 no.2
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• pp.135-145
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• 2018

In this study, we investigated the argumentations of group and classroom discussions in socioscientific issues (SSI) discussion classes. Twenty-seven high school students participated in the SSI discussion classes on nuclear power generation. We observed and recorded the classes and also conducted semi-structured interviews. For the analyses, we revised a previous framework that was developed to analyze dialogic argumentations in the context of SSI. The analyses of the results indicated that there were more discourse schemes in the classroom discussions than the group discussions which are related to awareness and openness to multiple perspectives, evidence based reasoning, and on-going inquiry and skepticism. And there were few discourse schemes related to moral and ethical sensitivity in the group and classroom discussions. Various grounds, data, and information were presented in the classroom discussions. Students concentrated on carrying their claims and were not able to sympathize with and accept other opinions. Therefore, there were few discourse schemes to reach consensus. In addition, they perceived classroom discussions as competitive and actively rebutted other claims or grounds. The levels of argumentation were also high in the classroom discussions. The group discussions were held in relaxed atmosphere, and they asked the opponents more for clarification or additional information and evidences. However, classroom discussions were held in serious atmosphere, and they actively queried the validity of the claims or grounds. Based on the results, some suggestions to implement SSI discussion classes were discussed.

• Journal of The Korean Association For Science Education
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• v.38 no.2
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• pp.249-257
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• 2018

The purpose of this study was to analyze the knowledge and ability levels of middle school students in four areas: conceptual understanding, argument construction, justification schemes, and use of scientific knowledge in a causal explanation for a genetic phenomenon. A group of 162 middle school students who have taken a class titled Genetics and Evolution participated in the study. Each student answered-and justified the answer to-one question pertaining to genetics. Ability levels were rated from level 0 to level 4, with 4 being the top rating. Students were required to choose one of two competing arguments to explain whether green seed pimps and red seed pimps of the same size and shape were the same species or not. Analyzing conceptual understanding: 47% of the respondents provided the correct answer. Analyzing their abilities for constructing an argument: 75% of the students with the correct answer and 42% of the students with the incorrect answer were evaluated to be at ability level 3 or 4 for argument construction. Analyzing the students' justification schemes: "Scientific idea" and "Analogy" were the most frequently used schemes. Analyzing their use of scientific knowledge: of the students who selected the scientific idea justification scheme, 36% used the correct scientific knowledge, but the remainder used inaccurate or nonspecific scientific knowledge. These findings provide implication for encouraging argumentative writing explaining scientific phenomena regarding epistemic practice.

• The Journal of Korean Association of Computer Education
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• v.11 no.1
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• pp.97-107
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• 2008

The result verification that determines correctness for the work results calculated in each PC is one of the most important issues in PC grid environments. In this literature, voting-based and trust-based schemes have been mainly used to guarantee the correctness of work results. However, these schemes suffer from both waste of resource utilization and high computation delay because they can not effectively cope with dynamic computational environments. To overcome these shortcomings, we introduce the distribution information of PC resources based on credibility and availability into result verification phase. Using this information, we propose a new result verification scheme, which can determine the correctness of work results by each PC resources' credibility and cope with the dynamic changing environments by each PC resources' availability. To demonstrate the efficiency of our result verification scheme, we evaluate the performance of our scheme from the viewpoints of turnaround time and resource utilization, utilizing resource distribution information in the Korea@Home that is a representative PC grid system in domestic. We also compare the performance of our scheme with that of other ones.

• The Journal of the Korea Contents Association
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• v.15 no.7
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• pp.30-42
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• 2015

In this paper, we propose a new skyline query processing scheme to enhance accuracy of query processing and communication cost in mobile P2P environments. The proposed scheme consists of three stages such as the pre-skyline processing, the query transmission range extension policy, and the continuous skyline query processing. In the pre-skyline processing, a peer selects the candidate filtering objects who have the potential to be selected. By doing so, the proposed scheme reduces the filtering cost when processing the query. In the query transmission range extension policy, we have improved the accuracy by extending the query transmission range. In addition, it can handle continuous skyline query by performing the monitoring after the first skyline query processing. In order to show the superiority of the proposed method, we compare it with the existing schemes through performance evaluation. As a result, it was shown that the proposed scheme outperforms the existing schemes.

• The Journal of the Korea Contents Association
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• v.6 no.9
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• pp.85-97
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• 2006

Schemes to case analysis and cope with on-line game crimes net supervision system, a real name confirmation process, and a self-examination system to check by themselves if they are addicted to on-line games with a view to prevent the addiction. In addition, this study found that general precuations should comprise measures to change the awareness of the users of the internet and to establish their ethical senses because most on-line garners are not aware that their actions are a crime and believe their crimes are not disclosed to the outsiders.

• The Journal of the Korea Contents Association
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• v.11 no.7
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• pp.70-79
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• 2011

The multi-path routing schemes that assigns labels to sensor nodes for the reliability of data transmission and the accuracy of an aggregation query over the sensor networks where data transfer is prone to defect have been proposed. However, the existing schemes have high costs for reassigning labels to nodes when the network topology is changed. In this paper, we propose a novel routing method that avoids duplicated data and reduces the update cost of a sensor node. In order to show the superiority of the proposed scheme, we compare it with the existing scheme through the various experiments. Our experimental results show that our proposed method reduces about 95% the amount of the transmitted data for restoration to node failure and about 220% the amount of the transmitted data for query processing over the existing method on average.

• The Journal of the Korea Contents Association
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• v.9 no.1
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• pp.139-146
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• 2009

This paper addresses a modified spectral subtraction schemes which is suitable to speech recognition under low signal-to-noise ratio (SNR) noisy environment such as the automatic speech recognition (ASR) system in car. The conventional spectral subtraction schemes rely on the SNR such that attenuation is imposed on that part of the spectrum that appears to have low SNR, and accentuation is made on that part of high SNR. However, such postulation is adequate for high SNR environment, it is grossly inadequate for low SNR scenarios such as that of car environment. Proposed methods focused specifically to low SNR noisy environment by using weighting function for enhancing speech dominant region in speech spectrum. Experimental results by using voice commands for car show the superior performance of the proposed method over conventional methods.

• The Journal of the Korea Contents Association
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• v.20 no.5
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• pp.1-10
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• 2020

In this paper, we propose a new pornographic content detection scheme using bi-directional relationships between neighboring auditory signals in order to accurately detect sound-centered obscene contents that are rapidly spreading via the Internet. To capture the bi-directional relationships between neighboring signals, we design a multilayered bi-directional dilated-causal convolution network by stacking several dilated-causal convolution blocks each of which performs bi-directional dilated-causal convolution operations. To verify the performance of the proposed scheme, we compare its accuracy to those of the previous two schemes each of which uses simple auditory feature vectors with a support vector machine and uses only the forward relationships in audio signals by a previous stack of dilated-causal convolution layers. As the results, the proposed scheme produces an accuracy of up to 84.38% that is superior performance up to 25.80% than other two comparison schemes.

• Journal of the Korean housing association
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• v.26 no.1
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• pp.1-10
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• 2015

In line with the recent public concern on the environmental issues in building industry, there has been a rise in demand for a healthy, sustainable housing environment in South Korea. In order to achieve a healthy environment in residential buildings, considerable efforts have been made in a wide range of sectors. Among others, the development of the certification schemes to promote environment-friendly planning and building construction is remarkable. In urban South Korea, recently built houses tend to be significantly high-rise, high-density buildings. Global warming has brought about drastic climate change and continued to increase the average annual temperature year by year. These changes should be well reflected on the government's implementation of the building environmental assessment system. For guidance, therefore, this study looks to the case of Hong Kong which is well known for high-density housing development and subtropical climate conditions. It compares the features of the green building certification schemes for newly developed multifamily housing in two regions, namely HK-BEAM in Hong Kong and G-SEED in South Korea. Based on the findings, it argues that the G-SEED implementor should have expanded roles in providing training programs and follow-up services in collaboration with the certification authorities. It is also argued that G-SEED professionals should be involved in the early stages of design processes, and training programs and licence systems to produce green building professionals should be developed. Finally, it points out that the assessment indicators should be more detailed and diversified.

• The Journal of the Korea Contents Association
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• v.11 no.1
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• pp.26-33
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• 2011

In ubiquitous environments that numerous mobile objects exist, the location-based services have risen as an important application field. For efficient location-based services, various techniques with broadcast schemes have been studied. However, they were mainly concerned with the implementation of a broadcast index and did not consider techniques for reducing the size of the entire broadcast data. Therefore, this paper proposes a data distribution broadcast scheme based on sensor networks that considers the mobile patterns of an object in road network environments. In this paper we also propose a road network based sensor clustering technique for the efficiency of the proposed distributed broadcast scheme. In order to show the superiority of the proposed scheme, we compare it with the existing broadcast scheme in various environments.